"Students don't get to choose when they have lectures. This proposal in its current form would still create barriers for students who have class early in the morning.
"A third of students at Vic travel during peak time, so we need concessions for them too."
The policy would also require cross-party support, and the association hoped to see that this election, Mr Zwaan said.
Students already get some discounts on bus and train fares -- up to 35 per cent in Auckland.
These discounted schemes had led to greater public transport patronage in the cities that offered them.
Dr Norman said the policy excluded peak-times because it would over-stretch the public transport system.
"When we looked at the public transport network, clearly the pressure is during the peak periods.
"The first step that we could take with relatively low-cost is about using the existing off-peak capacity."
The Student Green Card would be available to any person attending a university, polytechnic, wananga, private training establishment or New Zealand Apprenticeship scheme -- around 350,000 people.
The policy would cost the Crown an estimated $22 million to $28m annually -- less than the cost of one kilometre of one of National's roading projects -- and would be paid for by reprioritising spending from the National Land Transport Fund, Dr Norman said.
University of Auckland science student Monique Liebenberg, 20, said it would be her first time voting this year and the policy appealed to her.
"I'd use it on a daily basis. At the moment I spend around $7 a day on public transport, so I figure it would be good to save up that money and use it towards my studies."
Biology student AJ Essex, 22, said it would be good if the policy also covered students commuting to lectures at peak times, however free off-peak transport still provided students with "a lot more freedom".
The New Zealand Union of Students' Associations president Daniel Haines said the policy was a long-overdue acknowledgement that transport costs was a significant burden on students.